Donald McNeil's article on the apparent Taliban threat to the global polio eradication programme is spoilt by two inaccuracies. He asserts that my 1999 book "The River" is responsible for false rumours that modern polio vaccines are contaminated by HIV, and he claims that the central theory in the book has been "discredited". I pursued the allegations that Kenyans and Nigerians had refused polio vaccine because of my book, and I found that they were based on newspaper articles that didn't exist. Moreover, I have always stressed that, as far as is known, modern polio vaccines are safe. By contrast, I proposed in "The River" that the AIDS pandemic had been sparked by an experimental oral polio vaccine (OPV) that had been prepared locally in chimpanzee cells and then administered to a million Africans in the late 1950s. The growing tendency in science journals and recent books to assert that the OPV theory of AIDS origin has been refuted, and to enshrine the alternative bushmeat theory as fact, suggests an organised campaign of discrediting and misinformation. The latter theory proposes that the pandemic started when a bushmeat hunter or seller was exposed to infected chimp blood in south-eastern Cameroon around 1908, thus sparking an epidemic in Leopoldville (now Kinshasa), 500 miles away, which went unnoticed for 70-odd years. There is no hard evidence to support it: only phylogenetic theory based on a dubious model. By contrast with this shoddy science, the evidence for the OPV theory only strengthens.